But wyvern Elemental Breaths can Magic Burst.
Touche, I hadn't thought about that.
However, breaths don't even get a damage boost from being MB'd from what I have heard, which kinda defeats (part of) the purpose of MBing them to begin with =/
Also, DRG doesn't have direct control over what breath the wyvern uses anyway, and I don't think the wyvern considers SCs when using a breath either. The only thing you could do to force a breath MB would be to use the Drachen Armet to force it to use a specific breath that matches the target's weakness, and then make a SC that matches that element.
But I digress. In any case, I view the enfeebling boost from QD as the real point of the JA, not the direct damage :P Awesomeness of a potential "Dia IV" can't be denied!